Bulldozer blade



Jan. 17, 1956 Filed July 30, 195] J. F. CASSIDY BULLDOZER BLADE 3 Sheets-Sheet l Ja/m F msm'dy INVENTOR.

J. F. CASSIDY BULLDOZER BLADE Jan. 17, 1956 3 Sheets-Sheet 2 Filed July 50, 1951 John F. Cass/Hy [NI 'ENTOR.

Jan. 17, 1956 J. F. CASSIDY 2,730,823

BULLDOZER BLADE Filed July 30, 195] 3 SheetsSheet 3 John F. Gassidy INVENTOR.

WW Em United States Patent BULLDOZER BLADE John F. Cassidy, Kings Park, N. Y. Application July 30, 1951, Serial No. 239,225

2 Claims. (Cl. 37-444) This invention comprises novel and useful improvements in a bulldozer blade, and more specifically pertains to an improved structure and mechanism for supporting and manipulating the bulldozer blade and particularly in conjunction with power operating means powered by a tractor.

The principal object of this invention is to provide an improved mounting of a bulldozer blade upon a tractor and more specifically is to facilitate the angling and elevating of the blade, these operations being effected independently of each other or simultaneously as desired.

A further important object of the invention is to provide an improved construction for mounting a bulldozer blade upon a tractor to increase the rigidity of the blade, particularly against lateral stresses developed during angling and/or elevating of the blade.

A further important object of the invention is to provide an improved elevating mechanism for a bulldozer blade which shall be equally effective throughout the entire range of angling of the blade.

Yet another important object of the invention is to provide a more compact construction of a blade angling mechanism for a bulldozer blade, and to effectively conceal and protect the angling operating mechanism.

Still another important object of the invention is to provide an improved construction and manner for attaching the angling, supporting and elevating mechanism to a bulldozer blade for manipulating the same.

And a final important object of the invention to be specifically enumerated herein is to provide a mounting and operating mechanism for bulldozer blades which shall be more accessible for servicing or repairs, shall be more rigid, sturdy and dependable in operation than conventional mechanisms, and shall be inexpensive and easily installed.

These, together with various ancillary objects and features of the invention, which will later become apparent as the following description proceeds, are attained by the present invention, a preferred embodiment of which has been illustrated, by way of example only, in the accompanying drawings, wherein:

Figure 1 is a fragmentary top plan view of a portion of a conventional form of tractor having a bulldozer blade mounted thereon in accordance with the principles of this inveniton;

Figure 2 is a side elevational view of the construction shown in Figure 1;

Figure 3 is an enlarged vertical longitudinal sectional view, taken substantially upon the plane indicated by the section line 3-3 of Figure 1 and illustrating the internal construction of one of the blade supporting arms and a part of the angling mechanism of the same;

Figure 4 is an enlarged vertical longitudinal sectional view taken substantially upon the plane indicated by the section line 4-4 of Figure 1, and illustrating a portion of the blade elevating mechanism together with an extensible means therefor;

Figure 5 is an enlarged vertical transverse sectional view, taken substantially upon the plane indicated by the section line 5-5 of Figure 3 and showing certain internal details of construction of the support arm assembly;

Figure 6 is an enlarged fragmentary horizontal sectional view taken substantially upon the plane indicated by the section line 6--6 of Figure 2 and illustrating certain structural details regarding the pivotal mounting of the support arms upon the tractor;

Figure 7 is a perspective view of a rear section of one of the support arms;

Figure 8 is a perspective view of the front section of one of the support arms;

Figure 9 is a diagrammatic view illustrating in top plan the fluid conduit systems forming a part of this invention and illustrating in full and dotted lines various positions of the bulldozer blade obtainable by the: angling mechanism of the invention; and

Figure 10 is a perspective view illustrating a housing constituting a guard or shield for the flexible conduits of the angling mechanism.

Generally speaking, it is the primary intent of this invention to provide a structure and mechanism for mounting and manipulating a bulldozer blade upon a tractor in such manner that the blade may be readily angled, that is, caused to assume various inclined positions with respect to the longitudinal axis of the tractor; and wherein the blade may be readily elevated while being maintained in any of its desired angled positions.

It is to be understood that the embodiment disclosed in the accompanying drawings represents merely one suitable manner in which the principles of this invention may be employed; and although this embodiment discloses the use of hydraulic actuating means for various elements of this invention, it is evident that linkages, cables or various other operating mechanisms could be employed to effect the desired movements of the blade.

Referring now more specifically to the accompanying drawings, wherein like numerals designate similar parts throughout the various views, it Will be observed that there is disclosed at 10 in Figures 1 and 2 a portion of any conventional form of tractor, the same being illustrated as having the customary Caterpillar tractor treads, as including a tractor frame having side frame members 12, and as being provided with a conventional and known form of bulldozer blade 14.

An important feature of the present invention resides in the provision of separate and independent means for supporting and angling the blade With respect to the tractor, and for elevating the blade.

Blade supporting and angling mechanism As will be more apparent from Figure 1, the blade is supported, adjacent its extremities, upon the front ends of a pair of support arms, the latter being indicated generally by the numerals 16, the rear ends of these arms being journaled upon the frame of the tractor for vertical pivoting movement thereon. The journaling construction of the arms is disclosed in Figures 1, 3 and 6, it being observed that mounting plates 18 are detachably secured, as by fastening bolts or the like 26, to the side frame members 12 of the tractor, upon the outside surfaces of these frame members. Integral, horizontally disposed and laterally extending trunnions or pins 22 hav ing headed outer ends are carried by the plates 18, and constitute axles upon which the rear ends of the support arms 16 are journaled for vertical pivoting movement.

Referring now more specifically to Figures 3, 7 and 8, it will be apparent that each of the support arms 16 includes slidable, longitudinally extensible and telescoping rear andfront sections 24 and 26, respectively, these sections preferably being of a non-circular cross-section so as 3 to prevent relative rotation between the same but provid-- ing longitudinal, sliding and guided movement therebetween.

This telescopin construction not only; permits selective and independent lon itudinal adjustment of the sup ort arms" as desired arid as setfor'th' more specifically hereinafter, but further serves to reinforce and rigidify the support arms. As will be clearly apparent from Figure 3, the front end of the rearscction and the rear end of the front section are open for telescoping engagement, and for the reception andhousing of operating mechanism as set forth hereinafter.

At its rear end, the rear section 24 is reduced in crosssectional area, as shown. at 28,. and terminates in a hearing block or journal block 30 which is horizontally apertured for pivoting engagement upon the pin or trunnion 22'. -Conveni'ently,..the journal block 30 may be constructed in two halves,.one halfbeingintegral with the rear section. 24', while the other half may constitute a bearing closure cap, being detachably secured as by a plurality of bearing cap fastening bolts 32. By means of this detachable bearing assembly,the rear section may be read ily applied to or removed from the journal or trunnion pins 22, thereby facilitating the attachment of the bulldozer blade support arms to the tractor framework or their removal therefrom.

The front end of the front section 26 is likewise open, but has rigidly secured thereto a connector consisting of a body 34 which has a portion 36 of reduced cross-sectional area which is snugly'reeeived in the open end of the front section 26,: the junction of this reducedportion 36 with the body 34 forming a shoulder which is received against the open front end of the section-26 and is welded thereto. -Atits outer extremity, the body 34' is provided with a longitudinally extending. tongue 38', see Figure 8, which is apertured, asat 40, for the recep tion of a removable fastening pin 42, by means of which each connector 34 is detachably secured between a pair of vertically spaced parallel lugs 44 extending rearwardly from the bulldozer blade 14', these lugs being apertured to receive the above-mentioned fastening pin 42. It should behere noted that the fastening pin 42 has its axis vertically disposed when the support arm is in a substan tially horizontal plane, so'that the bulldozer blade 14 may be horizontally pivoted about its attachment to the support arm to thereby vary the angular inclination of the blade with respect to the longitudinal axis of the tractor. It will now be apparent that the bulldozer blade is attached to and supported by the tractor by this pivotal connection-at the pin 42.

The connector member 34 is in turn detachably secured to the end of a piston rod 54 in the following. manner. Upon its upper surface, the front end of the front section 26 is provided with an opening 46, see Figure 8, which is provided with a removable closureplate 48, see Figure 3. The reduced portion 36 of the connector 34 is recessed or slotted as'at 50 at itsinward extremity for the reception of an eyete'rminal 52 provided at the forward end of the piston rod 54, a fastening bolt 56 being movable through the opening 46 and being insertable through apertures in the portion 36, through the eye 52 for retaining the same in the recess 50, and has its'lower extremity screw-threaded for engagement in the bottom wall of'th'e member26.

Thus, the-bolt 56 serves the dual functions of securing the connector member 34' to the forward extremity of the front section 2'6', and further pivotally connects the front end of the piston rod- 54 to the connector and con sequently'to the front section 26L As will be readily appreciated, the member 34- could be secured and rigidly fastened to the" front section 26 in any other desired manner, but the construction above de scribed: facilitates the easy-removal of the-connection between: the blade 14' and thefro'ntsection 26; or betweenthe piston rod 54 and the member 34 or 26.

Upon its upper surface; the front section 26 is' further provided with a forwardly extending bracket 58 which overlies the upper surface of the front section and is apertured as at 60. Bulldozer blade brace rods 62 are provided, the same having an angulated extremity 64 receivable between the bracket 58 and the upper surface of the front section 26, and being" pivotally attached thereto as by a vertically extending fastening belt or pin 66. At its other extremity, the apertured end of the brace is pivoted as at 68' to pairs of support lugs 70 (see Figures 1 and 2) rigidly carried by the bulldozer blade 14. Preferably, the lugs 70 are disposed vertically above the connecting or hinge pins- 42 and substantially in or closely adjacent to the same vertical longitudinal plane extending through the central axis of the support arms 26.

It will now be apparent that various angular positions or inclinations of the bulldozer blade 14 with respect to the longitudinal axis of the tractor, or anglingof the blade, may be obtained by relatively varying the lengths of the two support arms I6. As illustrated in Figure9, the blade may be selectively positioned transversely per pendicular to the tractor with its axis disposed perpendicularly to the longitudinal axis of the tractor'as shownin full lines in Figure 9;. or, alternatively, may be positioned in reversely angled positions by properly adjusting the relative lengths of the support arms 16.to assume the dotted line position shown in Figure91 Obviously, various mechanisms can be provided for effecting the desired relative adjustment of the lengths of the support arms, and the principles of this invention are not limited to any particular adjustingmechanism. However, a very satisfactory power operating means for effecting the desired adjustments has been disclosed in the annexed drawings, the same employing the principles of hydraulic actuation for effecting with celerity, with certainty, and with perfect-control, the desired adjustments;

Housed Within the rear section 24 andpreferably closely adjacent but spaced slightly inwardly from the open forward end of the same is a hydraulic cylinder '72 of any conventionaldesign. If desired, this cylinder could be. formed integrally with the section 24," but it is preferred to employ a separate cylinder which-is'detachably secured and housed within the rear section. For this purpose, see Figures 3, 5 and 7, the rear section is providedwith a plurality of suitable apertures 74 for the reception of fastening bolts 76 which extend through these apertures and engage the cylinder 72 for detachably anchoring the same within the rear section. A conventional'piston, not shown, is slidably received within: the cylinder 72, and is adapted to be reciprocat'ed therein by the application of fluid pressure selectively upon opposite sides of the piston, the'latterhaving the above mentioned piston rod 54 attached thereto, this red extending. through the forward end of the cylinder 72' and into the hollow interior of the front section. 26; within which it is connected to' the same and to the connector 34 by the pin 56 as above mentioned.

It will now be apparent that when the hydraulic cylinder is, actuated, by a means to be later set forth, that either of the support arms may be selectively and adjustably longitudinally extended to manipulate'the' bulldozer blade 14* and position: the'same' at the desired angled position. It will be further apparent that the angling of the blade may beeffectedby properly manipulating-the controls ofthe hydraulic pressure means, withoutinterfering with the operation of the tractor, or the elevating or lowering-of the bulldozer blade by a mechanismto-b'e" subsequently set forth. 7

It should be here noted that itis in tendedto provide the hydraulic pressure conduits for actuating the' hydraulic cylinder 72, within the-interior of the hollow support arm 16,. and for this purpose each ofhollow support arms is provided with pressure conduits 78 and SWWhichre spee'tively communicate Wi'tlf rear and fi' brit iids of the cylinder 72, and to the rear and front faces of the piston reciprocable therein. These conduits extend through the reduced rear portions 28 of the rear sections 24 adjacent the journal bearings 30 thereof, so that the conduits and the hydraulic mechanism actuated thereby are completely housed within the telescoping hollow support arms whereby the same may be shielded against damage, and are protected against undue wear during operation.

It will be readily apparent that when the blade 14 is disposed in an angled position, a side thrust is imparted by the blade, during operation, to the support arms and to the connection of the same with the tractor. A brace means is provided specifically designed to resist this side thrust. This means, as shown best in Figure 2, consists of vertical plates 82, detachably secured as by bolts 84 or the like to the side frame members 12 of the tractor, these plates having vertical outside surfaces which may be slidingly engaged by the support arms 16 throughout the range of vertical pivoting movement of these arms, upon lateral displacement of the arms by virtue of the above-mentioned side thrust of the blade.

Shown clearly in Figure and indicated in Figures 1-3, is a shield or protective casing for the flexible hydraulic conduits '78 and 80, designated generally by the numeral 81 This includes a vertical metallic conduit section 83 having a mounting bracket or flange 85 Whereby the same may be secured to the side frame member 12. The section 83 has a horizontal extension 87 at its upper end which extends longitudinally of the member 12. At its outer end, the extension 87 has an upturned elbow 89 from which projects a horizontal tube 91 which rests upon and overlies the upper part of the member 12.

At its lower end, a semi-cylindrical plate 93 is pivoted to the vertical conduit 83, as at 95, and has a mounting flange 97 for attachment to the member 24.

The arrangement is such that the conduits '78, 80, emerg ing from the member 24, are received under the plate 93, extend through the entire protective casing 81 and from thence are conducted across the frame member 12 to the distributing valve 154 of the hydraulic operating system.

Blade elevating mechanism An operating mechanism, independent of that previous ly set forth for supporting and angling the blade, is provided for adjustably raising or lowering the blade. Re ferring more particularly to Figures 1, 2 and 4, it will be seen that there is mounted upon any suitable portion of the framework of the tractor, and between the sides of the same, a pair of elevating means which are operatively connected to the bulldozer blade 14, upon the rear side of the same, intermediate the ends thereof and between the connections of the blade with the support arms. It will be evident that various mechanisms could be provided for effecting the controllable lifting movement of the blade. Thus, a cable and pulley actuating system, a linkage system, and the like, could be employed, and the principles of this invention are not necessarily limited to any particular system. There has been shown, merely for convenience of illustration, a hydraulic system, and for this purpose a pair of conventional hydraulic cylinders 86, having pistons 88 reciprocable therein, are pivotally mounted as at 90 upon supporting brackets 92 suitably secured, as by fastening bolts 94, to any desired portion of the framework of the tractor. The pivot pins 90 are disposed with their axes in a horizontal plane in order to permit vertical pivoting movement of the cylinders 86 thereabout. The opposite ends of the cylinders 86 are closed so as to provide pressure chambers on opposite sides of the pistons 88, the latter having piston rods 96 which extend through the forward ends of these cylinders and are operatively connected to the bulldozer blade 14.

It will now be readily understood that by properly manipulating the pistons 88 within the cylinders, the blade together with the support arms will be caused to pivot upwardly about the trunnions or pivot pins 22. However,

it will be readily seen that the distance between these operating cylinders 86 and the blade 14 will necessarily vary, depending upon the angling of the blade 14 by the hydraulic cylinder 72 above mentioned. In order to accommodate this variation in the length of the connection between the elevating cylinders 86 and the blade, an elevating extension means is provided.

As shown more clearly in Figure 4, this extension means includes a connecting sleeve or bushing 98 which is internally threaded and at one extremity engages the end of the piston rod 96, while at its other extremity it threadedly engages the exteriorly threaded end of a rod 100. Suitable fastening bolts or pins 102 may be provided for positively locking the members 98, 96 and together in longitudinally adjusted position.

At its other end, the member 100 is provided with a plurality of longitudinally spaced apertures 104, and is slidably received within a bore or recess 106 in the rear portion of a fastener 108.

The member 100 is thus slidably received within the recess 106 of the member i108, the latter being provided with an eye 110 which is pivotally and detachably secured, as by a fastening pin 112, between a pair of vertically spaced lugs 114 attached to the rear surface of the blade 14.

A latch means is provided for adjustably and releasably retaining the member 100 in the member 108. For this purpose, the member 108 is provided with a supporting bracket or lug 116 to which is pivoted, as by a pin lid, an L-shaped lever having a latch arm 120 and an operating arm 122 which are disposed substantially at right angles with respect to each other. At its extremity, the latch arm 120 may have a finger portion 3.24, while a tension spring 126 may be terminally connected to this finger and to the member 108 for urging the latching arm about its pivot pin 118 and toward the member 103. Intermediate its ends, the latching arm has attached thereto by a pivot connection 128 a latch 130 which is detachably received in a diametrical bore 132 formed in the member 108 and one of the registering apertures 104 i in the member 100.

A control cable 134 is terminally connected to the operating arm 122, and extends to any convenient location upon the tractor for manual manipulation. by the operator of the same. Preferably, this cable extends through a housing 136 which is mounted upon the tractor, as by clamps 138 and bolts 140. The other end of this cable, as shown in Figures 1 and 2, extends from the other end of the housing 136, and is provided with a knob or the like 142, whereby the cable may be manipulated to efiect withdrawal of the latch 130 and thereby permit longitudinal adjustment of the extension of the elevating means.

Hydraulic fluid under pressure may be selectively applied to the elevating cylinders 86 at opposite ends of the pistons 88, as by flexible conduits 144 and .146.

Hydraulic operating n'zechanism The hydraulic system for controlling the delivery of hydraulic fluid under pressure to the angling mechanism and to the elevating mechanism may obviously be of various conventional types, and does not, in itself, form part of the invention claimed hereinafter. Disclosed in the diagrammatic view of Figure 9 is one arrangement intended to illustrate merely the principles of a satisfao tory hydraulic system. Suitably mounted upon the tractor at any convenient place thereon is: a conventional pump 148 for applying pressure to a hydraulic medium. By means of conduits 150 and 152, the hydraulic fluid under pressure is delivered from the pump 148 and is returned thereto from a combined fluid pressure reservoir and a fluid pressure distributing valve assembly indicated generally at 154.

Since hydraulic control systems of this general type are in themselves well known, the actual construction and operation of such a system forms in itself no part of this invention, and further explanation is believed to be unnecessary. a a

t Preferably, the hydraulic system and its control valve mechanism are 'so arranged that the operator may ind pendently or simultaneously operate the two elevating cylinders, or either singly or in unison the two hydraulic angling cylinders above described. Thus, the blade may be simultaneously vertically adjusted by raising ,or lowering while varying the angling or inclination of the blade during operation of the machine. I

The invention hereinbefore described thus permits a very rapid, easy and accurate adjustment of the elevation of the bladetand/ or its angling.

From the foregoing, the construction and operation of the invention, together with its many advantages will ,be readily apparent, and further explanation is believed to e unne es a y HQWeVelr i W91 610118 modi sat n and changes will readily occur to those skilled in the art after a consideration of the foregoing specification'and accompanying drawings, it is not desired to limit the invention to the exact construction shown and described, but all suitable modifications and equivalents may be resorted to, falling within the scope of the appended claims.

Having thus disclosed and described the invention, what is claimed as new is as follows:

1. A bulldozer blade construction for tractors comprising a pair of support arms mounted at their rear ends on the frame of a tractor, a bulldozer blade carried on vertical pivots by the front ends of said arms, fluid pressure means contained in said arms for selectively longitudinally extending said arms to elTect angling of said blade, journalling means on said frame journalling the rear ends of said arms for vertical pivoting movement, fluid pressure elevating means pivotally mounted on said tractor frame and operatively connecting with said blade intermediate of the connection thereto of said arms for vertical pivoting movement of the same, adjustable extensible means interposed between said elevating means and said blade for longitudinally varying the distance between said. elevating means and said blade, said extension means comprising pairs of longitudinally extensible telescoping members, said members. including aligning apertures, one of said members being pivotally attached tosaid blade,

and latch means pivotally mounted on one of said memvbers including a latch member engageable in said apertures for retaining said members in a fixed adjusted position and for permitting angling of said blade about said vertical pivots.

2. A bulldozer blade construction as set forth in claim i wherein said elevatingmeans includes pairs of hydraulic cylinders pivotally mounted on said tractor having reciprocal piston rods extending therefrom, fastener means pivotally connected to said dozer blade and including a longitudinal bore for reciprocably receiving an end of said piston rod, alignable transverse apertures contained in said piston rod andfastener means, a latch element pivotally mounted on said iastener means and including a latch member extendable through said aligned aper tures, a resilient member connected between said latch element and fastener means for urging the latch member into said apertures, and means operatively engageable with said latch element for overcoming said resilient memher and urging said latch member out of said apertures.

References Cited in the file of this patent UNITED STATES PATENTS 

